Analysis of sub-cerebellar regions in patients with Chiari Malformations

Engin Akar, Sadık Kara, Hidayet Akdemir, Adem Kırış


Chiari Malformations are serious neurological defects involving herniation of hindbrain tissues such as cerebellar tonsils, brainstem and IV ventricle into the spinal canal through the foramen magnum. By the severity of cerebellar descent, these malformations are classified into four different types. Clinically the least obvious and the mildest one is named as type I and defined as the descent of cerebellar tonsils into the cervical canal more than 5 mm. Magnetic Resonance Images (MRI) of brain in the sagittal plane provides the best clues in the diagnosis of the Chiari Malformation type I (CM-I). Previous studies investigated the morphological characteristics of cerebellum and nearby regions such as brain stem and fourth ventricle. Aim of this study is to analyze the cerebellar regions in chiari patients and healthy controls to search for the discriminative properties between the two groups. Sagittal brain MRI of eleven chiari patients and gender matched controls were used in order to examine the area of sub-cerebellar tissues such as gray matter (GM) and white matter (WM) and the area ratio between GM and WM. A graphical user interface (GUI) for implementing image processing techniques was developed using MATLAB environment. By means of GUI, the region embracing the whole cerebellum tissue on the mid-sagittal MR images were manually extracted. In addition, using Statistical Parametric Mapping (SPM) package the MRI slices were segmented into GM and WM tissues. Using the extracted cerebellum region as a mask, the cerebellar GM and WM tissues were achieved and the corresponding areas were computed by counting the number of pixels on each GM and WM slice. According to the statistical results, it has been found that cerebellar GM areas of the patients are significantly higher than the values of controls. As a consequence, this approach may provide a discriminative feature between patients with CM-I and health control subjects.
Keywords: Chiari malformation, magnetic resonance imaging, segmentation, gray matter, white matter

Full Text:



Choudhury PR, Sarda P, Baruah P, Singh S. A magnetic resonance

imaging study of congenital Chiari malformations.

OA Case Reports. 2013; 2(8):73.

Elster AD, Chen MYM. Chiari I malformations: clinical and

radiologic reappraisal. Radiology. 1992; 183:347–53.

Amer TA, el-Shmam OM. Chiari malformation type I:

a new MRI classification. Magn Reson Imaging. 1997;


Yassari R, Frim D. Evaluation and management of the Chiari

malformation type 1 for the primary care pediatrician. Pediatr

Clin North Am. 2004; 51(2):477-90.

Milhorat TH, Chou MW, Trinidad EM, Kula RW, Mandell

M, Wolpert C, Speer MC. Chiari I Malformation Redefined:

Clinical and Radiographic Findings for 364 Symptomatic

Patients. Congress of Neurological Surgeons. 1999;


Kunert P, Janowski M, Zakrzewska A, et al. Comparison of

results between two different techniques of cranio-cervical

decompression in patients with Chiari malformation. Neurol

Neurochir Pol. 2009; 43:337–45.

Nylan H, Krogness KG. Size of posterior fossa in Chiari type

I malformation in adults. Acta Neurochir (Wien). 1978;


Clatterbuck RE, Sipos EP. The efficient calculation of neurosurgically

relevant volumes from computed tomographic

scans using Cavalieri’s direct estimator. Neurosurgery. 1997;


Aydin S, Hanimoglu H, Tanriverdi T, Yentur E, Kaynar

MY. Chiari type I malformations in adults: a morphometric

analysis of the posterior cranial fossa. Surg Neurol. 2005;


Linge S, Haughton V, Løvgren AE, Mardal KA, Helgeland

A, Langtangen HP. Effect of tonsillar herniation on cyclic

CSF flow studied with computational flow analysis. Am. J.

Neuroradiol. 2011; 32(8):1474–1481.

Clarke EC, Fletcher DF, Stoodley MA, Bilston LE. Computational

fluid dynamics modeling of cerebrospinal fluid

pressure in Chiari malformation and syringomyelia. Journal

of Biomechanics. 2011; 46:1801-1809.

Nishikawa M, Sakamoto H, Hakuba A, Nakanishi N, Inoue

Y. Pathogenesis of Chiari malformation: A morphometric

study of the posterior cranial fossa. J Neurosurg. 1997;



  • There are currently no refbacks.